Driver/passenger-side airbags have been widely used as protective equipment in automobiles for protecting the occupant(s). In addition to front airbags, an airbag deployed on the side of a vehicle compartment are also being used. For example, a so-called curtain deployed to extend between a front pillar 11 and a rear pillar 13, as shown in FIG. 3, and a so-called side airbag provided on the side of a vehicle compartment have been developed and put into practical use.
Such a curtain airbag (hereinafter simply referred to as “airbag ”) 1 is comprised of an airbag main body 2 stored in the vicinity of a side roof rail (or a side roof panel) 12, along the longitudinal direction of the vehicle. When a high impact is applied to a side of the vehicle, such as during collision or the like, the airbag main body 2 is inflated to cover the overall side of the vehicle compartment to alleviate the impact on an occupant (more particularly, the impact on the head of an occupant).
A brief description will now be given of the mounting structure of the conventional airbag 1 with reference to FIGS. 4 and 5. FIG. 4 is a schematic side view showing a vehicle body 20 of an automobile, and FIG. 5 is a sectional view taken along line V—V of FIG. 4. As shown in FIG. 5, a center pillar 10 is comprised of an outer panel 10a disposed on the outer side of the vehicle and an inner panel 10b disposed on the inner side of the vehicle, and the edges (not shown) of the panels 10a and 10b, which edges extend in the longitudinal direction of the vehicle, welded to each other. In the upper part of the center pillar 10, the upper end of the outer panel 10a and a vehicle outer-side edge portion 12a of the side roof rail 12 are lapped one over the other and joined together, and the upper end of the inner panel 10b and a vehicle inner-side edge portion 12b of the side roof rail 12 are lapped one over the other and joined together. Further, a pillar trim 14 is disposed on the vehicle compartment inner side of the inner panel 10b in such a manner as to cover a vehicle compartment inner-side surface of the inner panel 10b. Further, the upper end of the pillar trim 14 is connected to a head lining 15.
The airbag main body 2 is disposed in a space between the pillar trim 14 and the inner panel 10b. As shown in FIG. 5, the airbag main body 2 is fastened on the inner panel 10b via a bracket 3 with a bolt 16 or the like. The bracket 3 is formed with a protrusion 31 extending substantially downward, and an engagement portion 14a, which is integrated with the pillar trim 14, is abutted against the protrusion 31. The airbag main body 2 is usually folded into a fan or accordion shape, or wound into a cylindrical shape.
A brief description will now be given of the operation of the curtain airbag 1 mounted as described above. First, in response to a side collision, the airbag main body 2 starts inflating to spread into the vehicle compartment from the space between the center pillar 10 and the pillar trim 14. Due to the impact of the side collision, the inner panel 10b of the center pillar 10 moves inwardly in the vehicle compartment as indicated by the arrow {circle around (1)} in FIG. 5. Since the center trim 14 is fixed to the inner panel 10b, the pillar trim 14 moves inwardly in the vehicle compartment with the movement of the inner panel 10b (as indicated by two-dot dash lines in FIG. 5).
As shown in FIG. 5, the airbag main body 2 is fastened on a point P in the upper part of the inner panel 10b and in the vicinity of the joint of the inner panel 10b and the side roof rail 12. As the point P has a relatively high stiffness, it is deformed to a relatively small degree even in the event of a side collision. Thus, the airbag main body 2 moves to a smaller degree as compared with the inner pillar 10b and the pillar trim 14. Therefore, the pillar trim 14 is likely to enter the inflating range of the airbag 1 in the event of a side collision, and the spreading airbag 1 can interfere with the pillar trim 14 to inhibit the airbag 1 from inflating in an ideal manner. In this respect, the engagement part 14a is designed to prevent the pillar trim 14 from entering into the inflating range of the airbag 1. That is, in the event of a side collision, the engagement part 14a, which is engaged with the protrusion 31 of the bracket 3, is designed to suppress the relative displacement of the airbag main body 2 and the pillar trim 14, thus preventing the pillar trim 14 from entering into the inflating range of the airbag 1.
According to the above described prior art, the engagement part 14a is required to have a high stiffness so as to inhibit the pillar trim 14 from entering into the inflating range of the airbag 1. Since the pillar trim 14 is ordinarily made of resin, however, it is difficult to provide the engagement part 14a with a high stiffness. Therefore, the prior art requires an additional L-shaped plate part to the engagement part 14a, and thus has the problem of increasing the number of parts and the weight. Incidentally, the related arts are also disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2000-168482 and Japanese Laid-Open PatentPublication (Kokai) No. 2000-33845. According to the related arts disclosed in these publications, as is the case with the above described prior art, a bracket for holding an airbag is fixed to a part in the upper part of a center pillar and in the vicinity of a side roof rail, and thus, it is impossible tom solve the above-mentioned problem.
Accordingly, there is a need to provide an occupant protective apparatus or arrangement that is simple in design and yet prevents a pillar trim from interfering with the airbag operation, thus enabling the airbag to inflate in a reliable manner. The present invention address this need.